From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1NrazH-0003L5-2Z
	for qemu-devel@nongnu.org; Tue, 16 Mar 2010 13:55:27 -0400
Received: from [199.232.76.173] (port=47699 helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1NrazG-0003KG-Ge
	for qemu-devel@nongnu.org; Tue, 16 Mar 2010 13:55:26 -0400
Received: from Debian-exim by monty-python.gnu.org with spam-scanned (Exim
	4.60) (envelope-from <jamie@shareable.org>) id 1NrazF-0005nj-6b
	for qemu-devel@nongnu.org; Tue, 16 Mar 2010 13:55:26 -0400
Received: from mail2.shareable.org ([80.68.89.115]:58136)
	by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32)
	(Exim 4.60) (envelope-from <jamie@shareable.org>) id 1NrazE-0005nf-TZ
	for qemu-devel@nongnu.org; Tue, 16 Mar 2010 13:55:25 -0400
Date: Tue, 16 Mar 2010 17:55:23 +0000
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] Re: [PATCH,
	RFC] Replace assert(0) with abort() or  cpu_abort()
Message-ID: <20100316175523.GD19160@shareable.org>
References: <f43fc5581003130656j408f64bfp7fe4bf486c625624@mail.gmail.com>
	<m3sk82nj16.fsf@blackfin.pond.sub.org>
	<f43fc5581003151023g354dc74cr989f3373f5f1de9a@mail.gmail.com>
	<m3vdcx8ma9.fsf@blackfin.pond.sub.org>
	<hnnf7e$8f9$1@dough.gmane.org>
	<m3ljds3auv.fsf@blackfin.pond.sub.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <m3ljds3auv.fsf@blackfin.pond.sub.org>
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Markus Armbruster <armbru@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>, qemu-devel@nongnu.org

Markus Armbruster wrote:
> Paolo Bonzini <pbonzini@redhat.com> writes:
> 
> > On 03/15/2010 07:36 PM, Markus Armbruster wrote:
> >> Please don't tell me that user emulators make abort() return.  abort()
> >> is declared __noreturn__, and the optimizer may well rely on that.
> >
> > If the user programs make a "signal (SIGABRT, SIG_IGN)" call, I
> > suppose abort() will return.
> 
> I program doing that gets what it asks for, and richly deserves.

A guest program is also allowed to trap SIGABRT with a signal handler,
and that does have some uses.  E.g. cleaning up temporary files and
shmem segments following a crash when calling 3rd party code.

Whatever the guest does with SIGABRT, it should not result in _QEMU_
crashing - whether due to abort() returning, or QEMU's control flow
jumping to the guest's signal handler from an unexpected location.

-- Jamie